Appreciate some help. Is it possible to execute a file with an .exe extension in DOS? If so, how is it done?

For example, have file, lets say: abc.exe on a floppy disk in the A:\ drive, and want to execute the file to drive D:\.

The PC in question has no OS at this time, just a PRI DOS partition, and an EXT DOS partition.

Any words of wisdom as to how this is done?